qusbglobal.h is not found.

[Arun-Dayal]

Describe the bug
When I build the example code I had got the following error
"the qusbglobal.h which has been included in the qusbdevice.h has not been found".

PLatform:

• OS: Ubuntu
• 18.04
  Qt version: 5.12
  To Reproduce
  Steps to reproduce the behavior:

1. Go to 'any example'
2. Click on 'build'
3. Scroll down to see qusbglobal.h is not found.

Additional context
I followed the instructions which has been mentioned in the read me for ubuntu and I also created a new project in qt and added the qtusb headers as mentioned in the Readme but I got the same build error as I have mentioned in the title.

[fpoussin]

Did you build and install the library first?